// construct and build DoubleArrayTrie dat = new DoubleArrayTrie(); for(String word: words) { dat.Insert(word); } System.out.println(dat.Base.length); System.out.println(dat.Tail.length); String word = sc.next(); // Look up a word System.out.println(dat.Exists(word)); // Find all words that begin with a string System.out.println(dat.FindAllWords(word));